1. Field of the Invention
The present invention relates to a connector, and more particularly to a connector in which double engagement is accomplished by first and second engagement means. The first engagement means is integrally formed in a connector housing, and terminals are inserted into terminal accommodation chambers provided longitudinally and laterally in the connector housing. The second engagement means is attached to the connector housing on an outer peripheral surface of the connector housing.
2. Description of the Related Art
Conventionally, a wire harness used for the electrical circuit of an automobile is connected with various electrical equipment through the engagement of male and female connectors. For example, in an instrument panel on which a large number of switches and meters are concentrated, a plurality of connectors are necessary. Thus, it takes much time and labor to accomplish the connection of the connectors, and the connectors occupy relatively large spaces. In order to solve the above problems, a compound type connector is used, in which a plurality of connectors, the sizes and shapes of which are different, are integrated into one body so that a large number of electrical connectors can be connected using one connector.
FIGS. 4 to 7 are views showing a compound type connector of the prior art (disclosed in Japanese Unexamined Patent Publication No. 62-188186).
As illustrated in FIG. 4, in this compound type connector, a male type connector housing 1 and a female type connector housing 2 are engaged with each other to electrically connect the terminals accommodated and held in the connector housings 1, 2.
In these connector housings 1, 2, terminal accommodation chambers 8, 9 for accommodating two types of female terminals 3, 4 and terminal accommodation chambers 10, 11 for accommodating male terminals 5, 6 corresponding to these female terminals 3, 4 are longitudinally and laterally provided.
In these male and female connector housings 1, 2, a large number of terminals are accommodated, so that a relatively large force is required for the connection of the connector housings. Thus, the engagement and connection of the connector housings 1, 2 are carried out in the following manner:
A fastening bolt (not shown) is arranged so as to penetrate through a bolt attachment section provided in the same direction as that of the terminal accommodation chambers 10, 11. Corresponding to the fastening bolt, a female screw member (nut) 14 is provided at a center of the male connector housing 1. The fastening bolt and female screw member 14 are screwed together.
The connector housings 1, 2 are each provided with double engagement mechanisms. Since both double engagement mechanisms are substantially the same, only the double engagement mechanism of the male connector housing 1 will be described below.
The width of the female terminal 3 is narrower than that of the female terminal 4. In the case of the male type connector housing 1, the narrow female terminals 3 are inserted into the three rows of terminal accommodation chambers 8 located in the first, second and third rows with respect to the right and left edges, and the wide female terminals 4 are inserted into the 3 rows of terminal accommodation chambers 9 located at the center of the male type connector housing 1. These terminal accommodation chambers 8, 9 are formed so that the inserted terminals are arranged in different directions, for example, the base plate portions of the female terminals 3, 4 are at right angles with each other. As illustrated in FIGS. 6 and 7, in these terminal accommodation chambers 8, 9, there are provided lances 16, 17, respectively, which are first engagement means for preventing the disengagement of the terminals. This is accomplished by engaging the lances 16 and 17 with the electrical contact sections 3a, 4a of the inserted female terminals 3, 4, respectively.
On the outer peripheral surface of the male type connector housing 1, there are provided engagement pin insertion holes 19, 20 for communicating a plurality of terminal accommodation chambers arranged in the same row. These engagement pin insertion holes 19, 20 are open for each row of the terminal accommodation chambers.
The second insertion engagement means 22 is attached to these engagement pin insertion holes 19, 20. As illustrated in FIG. 5, this second insertion engagement means 22 includes: a plurality of engagement pins 23, 24 for engaging the terminals 3, 4 accommodated and held in the terminal accommodation chambers 8, 9 when the plurality of engagement pins 23, 24 are inserted into the engagement pin insertion holes 19, 20; and a connecting section 26 for connecting the base end portions of the plurality of engagement pins 23, 24, wherein the engagement pins 23, 24 are arranged at the predetermined pitches corresponding to the arrangement of the engagement pin insertion holes 19, 20 on the connector housing 1.
As illustrated in FIG. 7, when the lance 16 is engaged with a punched hole of the base plate portion of the electrical contact section 3a of the female terminal 3, the disconnection of the female terminal 3 inserted into the terminal accommodation chamber 8 is prevented. The lateral section of the engagement pin 23 of the second insertion engagement means 22 is lozenge-shaped. When a fore end of the engagement pin 23 is engaged with a step portion at the rear of the female electrical contact section 3a accommodated and held in the terminal accommodation chamber 8, the disconnection of the female terminal 3 engaged with the lance 16 is positively prevented in the manner of double engagement.
The lateral section of the engagement pin 24 of the second insertion engagement means 22 is formed to be rectangular, and a constricted neck portion 4b of the female terminal 4 is pinched by the adjacent engagement pins 24. In this way, the double engagement is realized.
To be more specific, in the connector housing 1, after the female terminals 3, 4 have been attached into the terminal accommodation chambers 8, 9, the second insertion engagements means 22 is attached through the upper and lower peripheral surfaces of the male type connector housing 1, so that the double engagement is realized with respect to the female terminals 3, 4 accommodated and held in the connector housing 1. In this way, the female terminals 3, 4 are positively prevented from disconnection.
However, in the aforementioned double engagement mechanism, the connecting section 26 of the second insertion engagement means 22 is formed to be plate-shaped, so that the connecting section 26 is relatively flexible. Therefore, when the insertion pins 23, 24 are inserted into the corresponding insertion holes 19, 20, deflection may be generated in the connecting section 26. Accordingly, it is difficult to completely insert all of the engagement pins 23, 24 into the corresponding engagement pin insertion holes 19, 20 at the same time. For example, after the operation has been completed in which the engagement pins 23, 24 of the second insertion engagement means 22 are inserted into the engagement pin insertion holes 19, 20, it is necessary to investigate whether the connecting section 26 is flush with the sides of the housing 1 in order to be able to determine whether there is complete double engagement. However, it is difficult to determine whether there is complete double engagement based only on the disposition of the connecting section 26. The reason for this difficulty is explained below.
The sectional area of the engagement pin 23 of the second insertion engagement means 22 is smaller than that of the engagement pin 24, so that deflection tends to occur in the engagement pin 23. The disposition of the connecting section 26 may not be affected if, for example, the engagement pin 23 inserted into the engagement pin insertion hole 19 is deflected or a fore end portion of the engagement pin 23 is damaged. In that case, complete double engagement can not be realized, yet it is impossible to find the problem of an incomplete double engagement because the connecting section 26 is still flush with the side of the housing 1.